In general, a drinking water supply device is a device that supplies drinking water to a user. The drinking water supply device may be a stand-alone device, or may constitute part of an electric home appliance, such as a refrigerator.
The drinking water supply device may supply drinking water at room temperature to a user. In addition, the drinking water supply device may cool drinking water flowing therein using a cold water supply unit including a refrigeration cycle, or may heat the drinking water using a heater. That is, the drinking water supply device may supply cold water or hot water to the user as needed.
Drinking water may be underground water, raw water supplied from a faucet, or clean water obtained by filtering raw water supplied from the faucet using an additional filtering means, such as a filter. In the following description, however, drinking water will be defined as drinkable water. That is, drinking water is not limited to the above-mentioned kinds of water.
In recent years, there have been developed drinking water supply devices that are capable of providing functional water satisfying various demands of users in addition to the provision of filtered clean water, cold water, or hot water to users. For example, the drinking water supply device may include a mineral supply module in order to provide mineral water, which contains a predetermined amount of minerals, to a user.
Together with protein, fat, carbohydrates, and vitamins, minerals constitute the five types of nutritional substances. Minerals are known to play an important part in biochemical activity (e.g. catalytic activity) in the human body and in the constitution of the bones, teeth, etc.
In particular, calcium (Ca), potassium (K), magnesium (Mg), and sodium (Na) are mineral elements requisite for metabolism although it is sufficient to supply a very small amount of these mineral elements to the human body Mineral water, which contains such minerals, may play a supporting role in improving a user's health, such as discharging waste matter from the human body and promoting digestion.
In the case in which a predetermined amount of minerals are contained in drinking water, the water may taste better to a user than when the user drinks drinking water. In order to generate such mineral water, mineral supply modules, such as an electro-analyzer, a mineral filter, and a device for directly supplying condensed minerals to clean water, may be installed in the drinking water supply device.
In order to directly supply condensed minerals to clean water, it is necessary to provide a mineral container for storing condensed minerals and a mineral supply line connected between the mineral container and a drinking water supply line for adding the condensed minerals to drinking water. Meanwhile, the drinking water supply device may have a quantitative control mode, in which a predetermined amount of drinking water is supplied to a user, and a real time control mode, in which a desired amount of drinking water is supplied to the user in real time.
That is, in the quantitative control mode, the user may input a command through a quantitative control input unit provided in the drinking water supply device such that the drinking water supply device supplies a predetermined amount of drinking water to the user. On the other hand, in the real time control mode, the user may manipulate a drinking water discharge button or lever provided in the drinking water supply device, instead of inputting a command through the quantitative control input unit, such that the drinking water supply device supplies a desired amount of drinking water to the user in real time. In the real time control mode, however, it is not possible to determine how much water the user will discharge, with the result that it is difficult to determine when and how much minerals will be provided to water that the user will discharge.